Leveling apparatus and method



2 Sheets-Sheet 1 C B ANDERSON vLEIVELING APPARATUS AND IIETHGD April 18, 1950 Filed Feb 17 1939 April 18, 1950 C, B, ANDERSQN4 2,504,292

LEVELING APPARATUS AND METHOD Filed Feb. 1'?, 1939 2 Sheets-Sheet 2 y aan@ A,... is, mso

LEVELING APPARATUS AND METHOD Carl B. Anderson, Hessville. Ind.

Application February 17, 1939, Serial No. 257,011

9 Claims. (Cl. 205-1) My invention relates `to an apparatus and method for leveling or ilattening strip materials, more particularly for continuously leveling sheet metal strip of any desired temper or hardness by stretching the same, and my invention -h'as for an object the provision of an improved apparatus and method of this character.

It is an established fact that a maximum degree v of Iiatness may be imparted to sheet steel or similar sheet metal by properly stretching thesame, and apparatus has heretofore been provided for stretching and ilattening otherwise ilnished steel sheets which, during the forming and iinportions must be subsequently sheared 0K and 1 discarded. Thus a wastage of approximately 3" per sheet commonly occurs. Furthermore, since the sheets must be individually stretched after being cut to length, considerable timeis utilized in handling the sheets and in .adjusting the apparatus for each stretching operation.

It will thus be apparent that something is yetv to be desired in apparatus and processes for stretching and leveling sheet metal, and accordingly it is a further object of my intention to provide a continuous process, and an apparatus 'for carryingout such a continuous process, by

means of which steel or other metal `stripsfoi indefinite length may be stretched perfectly-flat without wa'stage so as to provide a more economical, a faster, and a more eiiiclent operation.

In carrying out my invention in one form, the metal strip to be flattened is continuously fe'd--at a predetermined rate to a set of gripping rollsf the peripheral speed of which is 4ailillsted'tof-a predetermined value in X$8 ofthe feeding rate` -the diameter of the intermediate roll and the intermediate roll being -positioned at one side of the outer rolls in offset relation thereto. Yieldable .means are provided for moving the intermediate roll toward andA away from the outer rolls to permit threading of the work material therebetween, the material being looped about the intermediate roll so that an increase in the tension of the-material during the ilattening operation urges the intermediate roll toward the two outer rolls more tightly to grip the material and prevent slippage, the yielding means permitting such movement of the intermediate roll.

In addition, driving means are provided which are adapted to drive the delivery rolls at a pre'- determined higher peripheral speed than the entry rolls, so as progressively to stretch the material a predetermined 'amount per lineal unit fand so flatten thematerial as it passes through the apparatus. In order to accommodate dinerent materials, means are -provided for adjusting the drivingmeans -to control the diiierential between the speeds of thel'two sets o f rolls, and particularly where hard types'of steel are to be ilattened a crowned member or crowned idler roll may be positioned so as to engage the strip material intermediate the entry and delivery rolls, the purpose of the crowned idler roll being to impart to the centerportion of the strip a greater degree of stretching thanis imparted to the edge portions thereof.

For a more complete understanding of my invention, reference `should now b ehad to the accompanying drawings, in which;

Figure 1 is a diagrammatic, perspective view of an apparatus embodying my invention, certain parts of the Aapparatus being omitted to illustrate 'the construction more clearly;

so as continuously to stretch the strip material a predetermined amount per lineal -unit and thereby iiatten it.

More particularly, I providefan apparatus com- -prising spaced-apart sets of entry anddelivery rolls for progressing the material to be ilattened. Each set of rolls includes a pair of outer relis jornaled on fixed axes in spaced-apartrelation land an intermediate roll journaled onanaxis which is adjustable at right angles to a plane v taken through the axes of the outer rolls, the peripheral spacing of the outer rolls being less than Fig. 2 is'an end elevational view illustrating diagrammaticallyone of the sets of gripping rolls shown in Fig. l; N

Fig.3.is asectional -view taken along the axis oi one of the rollsshown in Fig. i, illustrating the internal construction of certain of said rolls;

Fig. 4 is an illustrative diagram showing the interrelation of the various rolls and the work material during the operation of the apparatus illustrated in Fig. l; and

Fig. 5 is'an illustrative diagram similar to Fig. 4, showing another embodiment of my invention.

Referring-now to the drawings, in Fig. l I have shown my invention as embodied in an apparatus comprising -a base I0 having a plurality of rollsupporting housings il. l2 and I3 mounted along one side thereof, and it will be understood that 3 similar roll-supporting housings are correspondingly mounted along the opposite side of the base Il, these similar housings being omitted from Fig. 1 in order more clearly to illustrate the arrangement of the various rolls.

As shown, the housing I I supports a set of rolls I4, I* and I6, which are arranged to grip continuous sheet or strip material as it is fed to the apparatus. The two outer rolls I4 and I5 constitute bottom and top rolls, respectively, and are journaled on spaced-apart fixed axes supported in the housing Il, which housing is preferably so arranged as to permit ready removal of the rolls I4, I5 and I 6 for purposes of regrinding, etc.

The intermediate roll I6, which is adapted to cooperate with both of the outer rolls I4 and I5 in gripping material which has been threaded therebetween, is mounted on an axis that is adjustable horizontally, i. e., in a direction at right angles to a plane through the fixed axes of the rolls I4 and I5. This adjustment is preferably accomplished by yieldable means. Such means, which are illustrated in Fig. 1, may include a horizontally movable bearing support II and an air or hydraulic cylinder I'I and cooperating piston as will be clearly apparent to those skilled in the art.

Although rolls of any desired size may be employed, I have found it advantageous to utilize rolls having outer diameters of at least 16", so that sheet steel or smiliar material will not flute lwhen passing through and around the rolls. Preferably, the peripheral spacing of the fixed rolls is slightly less than the outer diameter of the intermediate roll I6, and accordingly the roll I6 is slightly offset from the fixed rolls I4' and I5, as shown in Figs. 1 and 2.

Adjacent the base Il) I provide a suitable gear housing I 8 in which is arranged a suitable variable speed transmission mechanism (not shown), which may be connected to an electric driving motor or other suitable source of power through a shaft I9. Each of the rolls I4, I5 and I5 is connected to the mechanism within the gear hous ing I3 by suitable connections, such as are respectively indicated by the reference numerals 20, 2| and 22. Each of these connections is preferably provided with two universal joints, some of which are indicated at 20e, 2|, 2Ih and 22", since, as indicated above, it may be desirable at intervals during the operation of the apparatus to grind the surfaces of the rolls I4, I5 and I6, and the roll I6 is horizontally adjustable as above described.

The roll-supporting housing I2 carries a set of gripping delivery rolls 23, 24 and 25. The arrangement of these rolls is substantially identical with that of the rolls I4, I5 and I6, with the exception that the movable roll 25 is disposed on the opposite side of the rolls 23 and 24, which are similarly mounted on spaced-apart fixed axes. As shown best in Fig. 2, the roll 25 is provided with suitable movable bearing supports indicated diagrammatlcally and designated by the referenceA numeral 25, which may be provided with yieldable adjusting means the same as is the roll I6 auch as a suitable air or hydraulically operated cylinder and piston arrangement.

The rolls 23, 24 and 25 are preferably so arranged as to provide for ready removal thereof for grinding purposes, and, as shown, are respectively connected in driving relation with the variable speed mechanism Within the housing I3 by means of connections 21, 28 and 23, which, like the connections 20, 2i and 22, are preferably 'provided with universal Joints, as indicated at Although any suitable type of variable speed gearing may be provided within the housing I8, I prefer to use dual type gearing, the mechanism being so arranged as to drive the delivery rolls 23, 24 and 25 at a peripheral speed which is higher than that of the entry rolls I4, I5, and I6. As will be explained more fully hereinafter, the differential between the speeds of the two sets of rolls determines the'amount of stretching that is imparted to the work material for leveling or flattening purposes. Thev changespeedgearing. contained within the housing I8 is arranged to provide a relatively large number of speed changes, so that the said speed differential may be varied in small steps between a desired miniv mum and maximum, thereby closely controlling the amount of stretching imparted to the work material by the operation of the rolls. Although any desired means may be utilized for controlling the speed changingmechanism, I have shown for purposes of illustration a pair of gear shifting levers 30 which may be suitably arranged to serve this purpose.

I have found that when a hard type of steel is to be stretched for atness, it is necessary to draw out the center of the strip more than the edge portions thereof. Accordingly I provide a crowned idler roll 3| which, as shown, is journaled in and supported by the housing I3 intermediate the entry and delivery rolls, and, as will be more apparent upon consideration of Figs. 4 and 5, this idler roll 3l is so located with respect to the entry and delivery rolls that the periphery of the idler roll engages the work material as it passes between the two sets of rolls, thereby imparting to the center of the strip a greater degree of stretching than to its edge portions. Preferably, the supporting housing I3 is arranged to permit the ready removal of the idler roll 3I so that it may be replaced with a similar roll having a greater or a less crown effect, in accordance with whether harder or softer steel or other material is to be passed through the apparatus.

Although, as indicated above, the entry rolls I4, I5 and I6 and the delivery rolls 23, 24 and 25 may be of any suitable construction, I have found it advantageous to so construct the movable rolls I5 and 25 as to provide for a certain amount of exure thereof. In Fig. 3 I have shown what I now consider to be a preferred type of construction for the rolls I6 and 25, said figure being a sectional view taken along the center line of the roll I6. As there shown, the roll IB consists of a hollow cylinder having a relatively thin wall, and I have found that for a 16" diameter roll a thickness of approximately ifs" or 1% ls suilicient. As shown, this hollow outer cylinder is supported at its opposite ends on suitable end members or discs 32 which may be secured to the hollow cylinder and to a coaxially extending shaft 33 in'any suitable fashion, as for example by welding. Intermediate the end members 32, I provide a plurality of annular disclike members 32* arranged in axially spaced relation to each other and secured at their outer peripheries to the inner wall of the hollow cylinder. y

These annular members 32B are preferably formed of steel or similar material and are of relatively thin construction, the inner diameter of each annular member being greater than the diameter of the shaft 33 to provide substantial clearance therebetween. In the embodiment shozwn, the members Haare preferably about W' in thickness, are secured to the hollow cylinder at axially spaced intervals of approximately l", Y

and have openings therein of sufficient diameter to provide a clearance of approximately l" between the shaft 33 and the inner edges of said openings. The annular members 32. while serving as stifieners for the hollow cylinder, are arranged to permit exure of the` cylinder relative to the shaft, `and I have found that the flexibility of the roll maybe controlled by varying the radial dimension, the thickness, or the axial spacing oi' these annular members. In some cases it may be desirable to utilize annular members of such reduced radial dimension as to provide a clearance of several inches between the shaft and the inner edges of these members.

With the rolls I6 and 25 constructed as shown in Fig. 3, a ilexible roll is provided so that if the material to be attened is, say. two or three thousandths of an inch heavier in some portions than in others, the rolls I6 and 25 bend sufficiently to nt the same and accordingly there is no-slippage on any part of the material as it passes through the entry and delivery sets of rolls.

Having in mind the above features oi' construction, it is thought that a complete understanding of my invention may now be had fromV a description of the operation thereof. Fig. 4 diagrammatically shows the entry rolls I4, I and I6, the delivery rolls 23, 24 and 25, and the idler roll 3I in substantially the relation illustrated in Fig. 1, and illustrates the operation of an apparatus of that type. The arrows applied to each of the rolls indicate the direction of rotation thereof, it being understood', of course, that the entry and delivery rolls are all positively driven, and that the rotation of the idler roll 3| is due entirely to the drag of the work material thereon. i v

Although the material to be stretched and attened may be supplied to the entry rolls of this apparatus from any desired source, such, for example, as the delivery rolls of a nishing mill, and the stretched and flattened material may be supplied from theA delivery rolls of the apparatus to any suitable storage means, I have shown for purposes of illustration a supply reel 34 from which continuous `sheet or strip material 35 may be supplied to the entry rolls I4, I5 and I6, and a similar take-up reel 36 for accumulating the material 35 after it has been stretched and flattened. l

Preferably, in order to guard further against manner shown, a portion of 'l hereafter,

and through the bight of the rolls I4 and I6. In order to accomplish this the roll Il is preferably moved away from the oils I4 and I5 by means of the yieldable operating means I'I. said operating means return the roll `I5 so as to grip the material tightly between the rolls I4, I5 and I6 in r for the operation of the apparatus. From the entry rolls the material 35 is passed over the idler roll 3i and is similarly threaded through the delivery rolls23. 24 and 25 in the the material being looped about the movable roll 25, which is also preferably withdrawn from the rolls 23 an'd 24 temporarily for threading pur ses.

o1' the material 35 is then connected to the takeup reel 3l.

due to the fact thatthe delivery rolls being determined by the differential in It will nowvbe apparent that, as the material passes through the apparatus, it is progressively stretched and therefore leveled or flattened are operating at a predetermined higher peripheral speed than the entry rolls, the degree of stretching the speeds, any desired gearing con- It will likewhich diierential may be adjusted to value by means of the variable speed tained within the gear housing I8. wise be apparent that since the material is pulled over the crowned idler roll 3| between the entry and delivery rolls, the centralportions of the sheet material are stretched to a somewhat greater degree than the edge portions thereof, this increased stretching of the central portions depending upon the amount of crowning of the idler roll 3|. Where such additional stretching is not desired, a substantially ilat idler roll may be utilized, or, if desired, this idler roll may be entirely omitted.

, 35 tends to move said rolls toward the associated slippage in any part of the apparatus, the tension on the supply and takeup reels should be maintained at a value nearly as great as the tension lexerted on the material between the entry and delivery rolls. Accordingly, the supply reel 34 may be connected in any suitable manner, indicated by a broken line 31, with a suitable drag motor 38 which may be of a type well known in the art, and the take-up reel 36 may be similarly connected, as indicated by a broken line 39, with a pulling motor 40. The drag motor 38 and .the pulling motor 40 may be controlled by any suitable means for regulating the forces exerted thereby, examples of which are, of course, well known in the art.

In the operation of my apparatus, as illustrated in Figs. land 4 particularly, the sheet material 35 is fed from the supply reel 34 about the top roll I5, through the bight of the rolls I5 and I6, is looped about the movable roll I6,

ilxed rolls I4, I5, and 23, 24, respectively, so as correspondingly to increase the gripping force exerted on the material by the rolls. Buch inward movement of the rolls I5 and 25 is of course permitted by the yieldable operating means I'I and 26, respectively, associated with these rolls.

In Fig. 5 I have shown a modified form of apparatus, which is substantially the same as that illustrated inFigs. 1 and 4 except that the movable rolls of the entry and delivery sets are disposed on the opposite sides of the xed rolls of said sets, and accordingly the material is threaded through the rolls in a slightly diierent fashion. In Fig. 5 corresponding parts are represented bythe same reference numerals -utilized in Figs. 1 to 4, inclusive, and the movable rolls corresponding to the rolls I6 and 25ct Figs. by the reference numerals I6 vand 25'.

The operation of the apparatus illustrated in Fig. 5 is believed to be apparent from the above description relative to Figs. 1 to 4, and it will be observed that here, again, any increase in the The end' tension of the material 35 tends to move the rolls IG' and 25' toward the associated ilxed rolls Il,

` I5, and 23, 24, respectively, so as correspondingly to increase the gripping force exerted by the rolls and thus prevent slippage of the material with respect thereto. As heretofore indicated, the peripheral spacing of the outer xed rolls, in both the entry and delivery sets, is preferably less than the diameter of the associated movable rolls. and this arrangement materially assists in preventing slippage by providing a wedge-like grip on the material passing between the rolls.

It will be apparent from the above description oi' my improved process and apparatus that my invention provides for the stretching of continuous sheet or strip steel or other material to a perfectly ilat condition and thereby affords a more economical, a faster and a more eflicient ilattening or levelling operation than has heretoiore been considered possible.

Although the non-slipping sets of rolls, as heretofore described, are of particular advantage when utilized in stretching and flattening apparatus embodying mv invention, it will be understood that this roll arrangement may be highly useful in various types of apparatus in which it is desired to prevent slippage. Thus, for example, non-slipping roll sets constructed in accordance with my invention may be utilized in a temper mill, in a strip washer, or in `any other type of machine where tension rolls are needed, and where it is desired to prevent slippage regardless of the pull exerted by the material passing through the rolls.

WLlle I have shown certain particular embodiments of my invention, it will be understood, of course, that I do not wish to be limited thereto since many modifications may be made therein. Therefore, I intend by the appended claims to cover any such modifications as fall within the true spirit and scope of my invention.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. In a flattening apparatus for sheet metal, spaced apart sets of entry and delivery rolls for gripping and positively progressing sheet material to be flattened, positively-acting driving means associated with said rolls for driving said delivery rolls at a positively predetermined higher peripheral speed than said entry rolls to stretch said sheet material solely by tension a predetermined amount per lineal unit as said material passes through said apparatus, and a crownshaped member engaging said sheet material intermediate said sets of rolls for imparting to the central portion of said sheet material a greater degree of stretching by tension than is imparted to the edge portions thereof.

2. In a flattening apparatus for sheet metal. spaced apart sets of entry and delivery rolls for gripping and positively progressing sheet material to be flattened, positively-acting driving means associated with said rolls for driving'said delivery rolls at a positively predetermined higher peripheral speed than said entry rolls to stretch said sheet material solely by tension a predetermined amount per lineal unit as said material passes through said apparatus, and a crowned idler roll engaging said sheet material intermediate said -sets of rolls for imparting to the central portions of said sheet material a greater degree of stretching by tension than is imparted to the edge portions thereof.

3. In a flattening apparatus for sheet material. spaced apart sets of entry and delivery rolls for progressing sheet material to be attened, eacli of said sets of rolls comprising a pair of outer rolls journaled on spaced apart fixed axes and an intermediate roll journaled on an axis adjustable at right angles to a plane through said flxed axes for gripping said sheet material between said rolls, the peripheral spacing of said outer rolls being less than the diameter of said intermediate roll and said intermediate roll being positioned at one side of said outer rolls, the path of travel of said sheet material through said sets of rolls comprising loops extending around said intermediate'rolls whereby an increase in the tension of said material urges said intermediate rolls toward said outer rolls more tightly to grip said material therebetween and prevent slippage, and driving means associated with said rolls for driving said delivery rolls at a predetermined higher peripheral speed than said entry rolls to stretch said material a predetermined amount per lineal unit as said material passes through said apparatus and thereby flatten said material.

4. In a flattening apparatus for sheet metal, spaced apart sets of entry and delivery rolls for progressing sheet material to be flattened, each of said sets of rolls comprising a three-high stand having top and bottom rolls journaled on spaced apart fixed axes and an intermediate roll journaled on a horizontally adjustable axis, the peripheral spacing of said top and bottom rolls being less than the diameter of said intermediate roll and said intermediate roll being positioned at oneside of said top and bottom rolls, the parts of travel of said sheet material through said sets of rolls being such that an increase in the tension cf said material urges said intermediate rolls horizontally toward said top and bottom rolls more tightly to grip said material therebetween and prevent slippage, and driving means associated with said rolls for driving said delivery rolls at a predetermined higher peripheral speed than said entry rolls to stretch said material a predetermined amount per lineal unit as said material passes through said apparatus.

5. In a ilattening apparatus for sheet metal, spaced apart sets of entry and delivery rolls for progressing sheet material to be flattened, each of said sets of rolls comprising a, three-high stand having top and bottom rolls journaled on spaced apart fixed axes and an intermediate roll journaled on a horizontally adjustable axis, the peripheral spacing of said top and bottom rolls being less than the diameter of said intermediate roll and said intermediate roll being positioned at one side of said top and bottom rolls, the path of travel of said sheet material through said sets oi' rolls being such that an increase in the tension of said material urges said intermediate rolls horizontally toward said top and bottom rolls more tightly to grip said material therebetween and prevent slippage, driving means associated with said rolls for driving said delivery rolls at a predetermined higher peripheral speed than said entry rolls to stretch said material a predetermined amount per lineal unit as said material passes through said apparatus, and

means for adjusting said driving means to vary the differential between said peripheral speeds of said sets of rolls to control the degree of stretching imparted to said sheet material.

6. A stand of driven gripping rolls adapted to progress sheet material under tension comprising a pair of outer rolls journaled on spaced apart xed axes, an intermediate roll having a diammoving said intermediate roll away from said outer rolls to permit threading of said sheet material therebetween, said material being looped about said intermediate roll, said yieldable means also being eifective to move ,said intermediate roll toward said outer rolls tightly to grip said material as said rollsare driven, said yieldable means upon an increase in the tension of said sheet material permitting further movement of said intermediate roll toward saidouter rolls by said tension more tightly to grip said material and prevent slippage thereof relative to said rolls.

7. A flexible gripping roll for use in a stand of tension rolls for sheet metal strip, comprising a central shaft, a pair of end members rigidly secured to said shaft in spaced apart relation to each other, a relatively thin metal cylinder supported on said end members in coaxial Jrelation to said shaft, and a plurality of annular disc-like stiiening members surrounding said shaft in spaced relation thereto, said annular members being secured to the inner surface of said cylinder in relatively closely spaced axial relation to each other and being relatively very thin as compared with their radial extent.

8. Afiexibleroll forA sheet metal work having a working surface comprising a hollow cylindrical member capable of fiexure, a shaft, spaced apart supporting means for mounting said cylindrical member on said shaft in coaxial relation, and av plurality of annular disc-like members secured to,

the inner surface of said cylindrical member in relatively closely spaced relation, said disc-like members surrounding said shaft and having internal diameters greater than the diameter of said shaft and being relatively very thin as compared with their radial extent.

9. A flexible roll for sheet metal work comprising a relatively thin walled cylinder, a plurality of annular discs secured to the inner surface of said cylinder in relatively closely spaced axial relation to each other, said discs being relatively very thin as compared with their radial extent, a shaft extending through said annular discsin spaced relation to the inner edges thereof, and

vsupporting members secured to said shaft and Y said cylinder adjacent the ends thereof for mounting said cylinder on said shaft in coaxial relation thereto.

CARL B. ANDERSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number y Name Date 408,219 Curtin Aug. 6, 1889 437,413 Eckerson Sept. 30, 1890 672,516 Schinneller -1 Apr. 23, 1901 723,682 Kortright Mar. 24, 1903 1,200,076 Burgess Oct. 3, v1916 1,239,175 Gilbert Sept. 4, 1917 1,467,880 Roemer Sept. 11, A1923 1,490,549 Woodworth Apr. 15, 1924 1,584,499 Zachhuber May 11, 1926 1,624,394 Cronk Apr. 12,1927 1,923,738 McBain Aug. 22, 1933 1,986,776 Moore Jan. 1, 1935 2,040,442 Nieman May 12, 1936 2,073,174 Potter Mar. 9, 1937 2,140,533 MacChesney Dec. 20, 1938 FOREIGN 'PATENTS Number Country Date 168,501 Switzerland July 2, 1934' 453,643 Great Britain Sept. 14, 1936 463,374

Great Britain Mm. 30, 1937 Certcate of Correction Patent No. 2,504,292 April 1s, 195o CARL B. ANDERSON It is hereby certiied that errors appear in the printed specification of the above numbered patent requiring correction as follows:

Column 1, line 17, for the Word exerted read escertfzlng; column 8, line 34, for parts read path;

and that the said Letters Patent should be read With these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 1st day of August, A. D. 1950.

THOMAS F. MURPHY,

Assistant Oommz'ssioner of Patents. 

